Outside / inside floors, how can they be the same level?

[besmirchedandbewildered]

I'm having an extension built with folding/sliding doors to the outside. Every magazine I see shows pictures of houses where the patio and inside floor are flush with a drain down the middle, so the floor levels are the same inside and out. My builder is telling me that the damp proof course has to be higher than the patio and therefore there has to be a step down from inside to outside. Why is he saying this and how can I get around it?

Bumps hopefully? Has anyone else come across this problem and did you manage to resolve it? Thanks

I don't know how you do it, but I do know that many houses have level access, so there must be a way!

Snap! there IS a way round it but I can't remember what my builder said (we in the early stages and I am already overwhelmed! I think you can have a drain put in (I think he said something about a french drain?) or you can have decking built up to your doorway (basically your house can breath under the decking).

It is possible - your builder should be able to give you the options available.

Your builder is right to keep your DPC open to air, but my guess is that as long as there is a drainage channel between the door and the patio which you would cover with a grid, it would be doable. The patio should slope down away from the house into soil wherever possible.

Thank you, will try again, I was pretty sure I wasn't asking the impossible and you have confirmed it

My friend wanted this in her current renovation but Building Control made her put the patio 75mm below the threshold to her home to avoid flooding potential I think (she doesn't live in a flood risk area) - perhaps it's a new building reg.

Oh bugger. Will have to ring Building Control I think. I just can't believe there isn't a way round it :(

We are having building work done at the moment and the plan is for level threshold. I didn't listen to the details enough but as I understand it, it's pretty much what achillea said - drainage channel between door and patio, patio sloping slightly away from house.

Hi,
Has anyone else had this done? A patio directly outside bifold doors that is level with the inside floor level?
Is it ok to cover the dpc level using a channel drain with gravel below?
Thanks!

You can do this but it's vitally important to get the detailing correct to avoid rising damp or puddles inside.
You need to have airflow under the decking to ventilate the area by the dpc & you need as others have said a French drain (or similar) with a slightly sloping patio(away from the house) to avoid rainwater coming in.
A lot of people (even professionals) say it can't be done because it's much more work (both physically & on working it out) and they can't be arsed.
It can be made to meet BRegs to as otherwise we'd never be able to make accessible entrances which are required on non domestic buildings under part M of the building regs.

We really wanted this and our window/door company refused to do it as they had an incident where water leaked into the kitchen with the flush threshold. Now they put an aluminiam threshold...
so when the doors are open we have the tiles flush up to the bifolds and then there is the aluminium threshold which is sort of sloping down to the patio slabs. This will be flush with the patio slabs. So there is a slight step, probably about 20mm.

In order to do this flush without a step down, you do have to put a drain in. It's called an Aco drain. In fact, we have to put an aco drain in anyway I believe in order to not leave 2 courses of engineering bricks. So we are having this outside the bifolds and the other french doors. Then one french door we are leaving 2 courses of bricks so we don't have to have a drain.

I really really wanted flush and was convinced otherwise. For us, it's best to have this aluminium threshold because we are completely open to the elements as it is open onto fields at the back so the wind/rain etc hits the doors hard. So consider how the weather will hit your bi-folds too.
It doesn't look as nice as the flush I do have to admit but I prefer that than risking any flooding.

Sorry this may sound confusing reading back but hope it helps a bit!